Fuel injection system device (Mondeo 3)

Under the bonnet of a modern car, electronically controlled fuel injection systems have long been the "tone-setter" in the intake tract of petrol engines. On the exhaust side, there is a state-of-the-art three-way catalytic converter. So, no questions asked, all Mondeo power units: "from the air filter to the exhaust pipe" are controlled electronically: the required fresh fuel mixture is prepared by sequential fuel injection systems, assisted in this process by a three-way catalytic converter. The ignition sparks are controlled by distributorless ignition systems in the sequence 1-3-4-2 (Duratec-HE) or 1-4-2-5-3-6 (Duratec-VE). They are, like the entire electronic engine management, controlled by a powerful on-board computer (PCM). The new Mondeo has "Black Oak", a new generation engine management system that supervises the "bits and bytes". Black Oak, developed by Ford subsidiary Visteon, works in conjunction with a 32-bit Levanta computer, including a Motorola processor and a CAN data bus. In its operation, Black Oak resembles the previously used EEC engine control system.
PCM control unit with 32 bits and CAN bus for data transmission

1 — Absolute pressure sensor in the intake pipe with a built-in intake air temperature sensor (TMAP), 2 — Throttle position control sensor (TP), 3 — Coolant temperature sensor (ECT), 4 — Crankshaft position sensor (CPS), 5 — Camshaft position sensor (CMP), 6 — Outside air temperature sensor (AAT), 7 - Pluggable and heated Lambda sensor (HO2S), 8 — Hydraulic servo control switch (PSP), 9 — Vehicle Speed Sensor (VSS/OSS), 10 — Clutch pedal position switch (CPP), 11 — Generator regulator (Smart Charge), 12 — Knock sensor (KS), 13 — Power supply relay, 14 — battery, 15 — Automatic transmission (CD4E), 16 — MTL indicator lamp,

17 — Transmission Control Module (PCM), 18 — Diagnostic connector (DCL), 19 — Fuel pump relay, 20 — Fuel tank pump, 21 — Nozzle, 22 — PATS LED (instrument panel), 23 - EGR stepper motor, 24 — Idle Air Control Valve (IAC), 25 — Swirl flap electromagnetic valve, 26 — AC compressor, 27 — Generator regulator (Smart Charge), 28 — Ignition coil, 29 - Electrically heated thermostat, 30 — Solenoid valve of activated carbon filter, 31 — VSS/OSS output signal (instrument panel).

Sensors and actuators under the engine hood

1 — Engine control unit, 2 — Crankshaft position sensor (CPS), 3 — Solenoid valve of activated carbon filter; 4 — Camshaft position sensor (CMP), 5 - EGR step-by-step engine,	6 — Coolant temperature sensor (ECT), 7 — Throttle position control sensor (TP), 8 — Idle Air Control Valve (IAC), 9 — Swirl flap electromagnetic valve, 10 - Absolute pressure sensor in the intake pipe with built-in intake air temperature sensor (TMAP), A Hydraulic servo switch (PSP).

Electronic engine control is not for independent users

New systems require little maintenance – in practice, any possible malfunction can only be detected by a competent specialist with the necessary measuring equipment. This fact places increased demands on those who want to do the repair themselves – Ford workshops rely on the "WDS-Diagnose CD B8" when checking the engine. Therefore, if there are any faults in the engine management system, it is better to entrust your Mondeo to specialists. However, you should still know the basic principles of preparing the combustible mixture of your Mondeo. And only on this basis will you be able to accurately classify the faults that arise. Thanks to this, you will save on expensive diagnostics. In addition, you will be able to clearly formulate an order for repairs, and the resulting calculation will not raise any doubts in you. As an example for Ford petrol engines, detailed information on preparing the fuel-air mixture of the Duratec-HE power unit is provided below.

Detailed information about the Duratec-HE injection system control

The PCM control unit (integrated into the PATS): this is the central unit of the electronic engine management. The on-board computer constantly uses the current "data material" from its spatial parametric characteristics (rotation speed, intake manifold pressure, intake air and coolant temperature, etc.) and compares them with the fixed parameters in the database. After this comparison, the control unit determines and calculates, among other things, the duration of the opening of the electromagnetic injector, the volume of fuel required and the composition of the air-fuel mixture. At the same time, the PCM unit is reprogrammable: an essential criterion for situations when it starts the next calibration moment with modified parameters.

Advantage: with the help of the Ford mobile diagnostic device "FDS 200" it is easy to erase the electronically reprogrammable read-only memory (ROM) and "fill" it with a new engine management program. The corresponding service module for the PCM is already installed at the manufacturer. The 16-pin diagnostic connector (DLC) is "hidden" in the left footwell at the height of the fuse box.

Fuel injection system safety switch: located on the side of the left door. This switch can be used to interrupt the fuel supply if there is a leak in the fuel supply system, during an accident or in the event of a severe collision. Interruptions in the electrical circuit are recognized by the pop-up switch button. Before activating the safety button, first check the fuel system for leaks, then turn the ignition switch to position "0" and press the button. Then turn the ignition key to position "II" for a few seconds and then turn the switch to position "I".




Crankshaft Position Sensor (CPS): in Duratec engines it is located on the control unit cover on the side of the crankshaft shock absorber. The sensor is on the toothed wheel (36 teeth minus 1; "tooth gap" for the 1st cylinder is 90° from TDC) inductively registers the exact angular position of the crankshaft, as well as the current engine speed, these measured values affect:

• injected fuel and start of injection,
• ignition timing and
• idle speed control.

If the CKP sensor fails, all engine control switches to "deep sleep": the engine stops and remains "mute" until the sensor is replaced.

The gap between teeth 1: 90° from TDC of the first cylinder.

Camshaft Position Sensor (CMP): in Duratec engines it is located in the cylinder head in front of the first cam of the intake camshaft. The sensor works on the basis of the inductive principle. Its signal is used by the CMP to recognize the 1st cylinder. It controls the sequential injection of fuel.

Coolant Temperature Sensor (ECT): "inserted" under the ignition coil and measures the coolant temperature in a small circle.

Manifold Absolute Pressure Sensor with Built-in intake air temperature sensor (IATS). The TMAP sensor helps to minimise possible power losses when driving on mountainous sections of road or downhill. It determines the current prevailing operating state of the engine with the ignition on and full load. The atmospheric pressure in the intake manifold is used as a measured value by the sensor. These parameters are saved and processed by the PCM as a reference pressure for the corresponding pressure in the intake manifold under different load conditions. The signals from the integrated IAT sensor are initially only basic values when starting a cold engine or during the warm-up period. In addition, they are used by the MAP sensor as correction parameters, since it compensates for the different degrees of filling of the cylinders using its "internal knowledge". Based on all input signals from the TMAP sensor, the PCM calculates the air mass required by the engine.



Knock Sensor (KS). The knock sensor is a "mechanical vibration sensor". Duratec engines are equipped with such sensors due to their relatively high compression ratio. This sensor is located on the intake side directly on the engine cylinder block between the second and third cylinders. When mounted, it should not come into contact with the surrounding "mass" under any circumstances.

As soon as the "detonation limit" is reached, the KS sensor sends signals to the SKR and SMR sensors about uncontrolled combustion of the hot mixture. Based on these signals, the PCM shifts the ignition advance angle back by 1.5°. If the signals continue, the angle continues to decrease until the combustion process is normalized. If detonation noises do not appear within two seconds, the PCM adjusts the ignition timing to the detonation limit or - with standard fuel quality - to the prescribed ignition timing.

Knock sensor: permanently at the listening post.

Throttle Position (TP) Sensor: This sensor is bolted to the throttle body. It functions in the same way as a rotary potentiometer and affects:

• idle speed,
• composition of the intake combustible mixture (14.7: 1),
• exhaust gas regulation and
• opening of the system control loop.

Power steering pushbutton switch (PSP). It takes its information from the pressure line between the hydraulic power steering pump and the steering gear. As soon as the pressure drops, for example when maneuvering the car with the steering wheels turned all the way, the PSP opens and signals the PCM to slightly increase the idle speed.

Pressure Controller: Push-button switch for power steering.

Lambda sensor (HO2S): Duratec engines are equipped with two lambda sensors at the factory. Sensor 1 is located directly in the exhaust manifold, sensor 2 in the outlet pipe behind the catalytic converter. Both sensors analyze the residual oxygen content in the exhaust gas and transmit this information to the PCM. Their signals affect:

• the amount of injected air and
• operation of the EVAP system.

Cleaner: HO2S lambda sensors. 1 — Front lambda sensor, 2 — Rear lambda sensor, 3 - Catalyst, 4 - Additional muffler.

Lambda sensors have a strong influence on the function and service life of the catalytic converter. They provide information on the constant changeover of slightly enriched and lean fuel mixture for the proper functioning of the catalytic converter. In combination with the automatic CDE4 system, exhaust gas filtration is also performed by an additional starting catalytic converter, which is located directly in the exhaust manifold.

Idle Air Control Valve (IAC). In Duratec engines, this valve is located near the throttle valve on the intake manifold. The PCM controls it using timing signals. Depending on the frequency of the signal, more or less fresh air bypasses the throttle valve via the diverter valve.

The swirl flap solenoid valve is positioned at an angle behind the IAC valve in the intake manifold. Its control pulses are based on engine speed and throttle opening angle: depending on the situation, the valve is "empty" or "full".

In close proximity: 1 - Idle Air Control Valve (IAC) and 2 - Swirl Flap Solenoid Valve.

Carbon Filter Solenoid Valve. In conjunction with the Black Oak engine management system, the 2000 Mondeo uses a redesigned solenoid valve. Under certain operating conditions, it opens and releases fuel vapors from the filter to the intake manifold.

EGR stepper motor: The stepper motor is located at the rear end of the cylinder head and reacts sensitively to digital signals from the PCM. In other words: the stepper motors of the Duratec power units implement very small stepping movements. In addition, compared to conventional drives, they are not sensitive to vibrations and pressure fluctuations during operation. The spindle converts the rotary movements of the stepper motor into a lifting movement, due to which the valve is precisely opened. This feature not only improves the operating principle of the exhaust gas recirculation, but also makes additional components, such as a differential exhaust gas valve (DPEF), unnecessary.

EGR stepper motor

Not sensitive to vibrations and pressure fluctuations.

A – to the suction system, B - from the exhaust manifold, 1 - Electrical connection, 2 - Stepper motor, 3 - Stepper motor spindle,	4 - Pressure spring, 5 — Valve spindle, 6 — Valve seat, 7 — Valve seat.

Injectors: The injectors with four injection holes and side fuel supply are located in a common fuel distributor tube. The PCM sequentially controls the injectors. Their nozzles are installed at strictly defined angles so that two holes of the right and two holes of the left valve "meet" accordingly.

Shoulder to shoulder: injectors with four injection holes 1 and side fuel supply are located in a common distributor tube 2.

Outside Air Temperature Sensor (AAT). The outside air temperature sensor is hidden in the buffer on the front left. Its signal controls

• outside temperature indicator on the instrument panel,
• generator regulation (Smart Charge) and
• air conditioning.

Overdrive Speed Sensor (OSS) and Vehicle Speed Sensor (VS): The signals from both sensors are processed by the PCM to regulate air flow in the idle air control (IAC) system, to enrich the air-fuel mixture during acceleration and forced idle mode.

Possible with restrictions - self-help with injection system

As already noted in the introduction to this manual, most work with the injection system is best left to professionals. They have the necessary control devices and the relevant knowledge. For example, if there are faults in the electronic engine management system and in order to properly localize them, it is necessary to carry out a series of tests in a certain sequence. This is the only way to identify the defects and their consequences and prescribe a course of repair work. Having ordinary "home" knowledge is not enough to work with the Mondeo injection system. But there is no reason to "panic": in practice, possible damage to this system is rare.


This publication was borrowed from the website FORDBOOK.RU